Although this doesn't look much like water, its still a pretty cool abstract effect!
Step 1
Create a new image, I filled the background with a blue/dark blue gradient - do as you wish.
Step 2
Create a new layer, and with the paintbrush tool create white lines similar to the above picture.
Step 3
Go into the liquify menu, shown above.
Step 4
On your white-line layer, liquify it to look something like this.
Step 5
Double click your liquified, white-line layer and adjust the blending settings to the above (Just change to overlay)
Step 6
On the current layer, go to the wave distortion filter shown above
Step 7
Inside the wave filter, use the above effects.
Step 8
Copy your current layer.
Step 9
Apply the above wave-distortion filter settings to the new layer
Step 10/Final Product
Copy your new layer multiple times and move around the image to create the above image (or something similar). Try experimenting!
If you have any questions or comments, please post below so we can help!